The present invention relates to a delivery system with increased bioavailability. Many active agents are substantially biologically inactive in their dry form. One way of delivering biologically active agents of this type is in the form of a liquid, such as through the use of liposomes.
However, consumers typically prefer to take such active agents in the form of a tablet or other solid dosage form. This obstacle has been overcome by using conventional forms of encapsulation. A variety of chemical compositions are conventionally used as encapsulating agents to deliver dry material in, inter alia, the food, cosmetic, paint, pharmaceutical, personal care, household, and polymer industries. Typical compositions which conventionally function as encapsulating agents include gum arabic, dextrins, starches, arabinogalactan, gum acacia, casein, gelatin, carboxymethyl cellulose, tragacanth, karaya, sodium alginate, tannin, and celluloses. While these compositions are successful in transforming the active agent into a dry powder, they do so as a substantial cost to the bioavailability.
Surprisingly, it has now been discovered that the present invention which uses a modified starch, prepared by enzymatically converting a starch after the preparation of a starch derivative containing a hydrophobic group or a hydrophobic and a hydrophilic group, as an encapsulating agent consistently allows for high bioavailability.